The invention relates to the field of collator apparatus, i.e., sorting devices for sheet material as used extensively to produce multiple collated sets of multipage documents which have been printed or copied.
Various collators or sorting apparatus are known in the art. Cross-referenced patent application Ser. No. 752,777, filed Dec. 20, 1976, entitled "Virtual Bin Collator Control" describes a method and apparatus for controlling a multibin sheet collator and contains a discussion of the prior art relating to such apparatus.
A copy production machine suitable to operate either in a simplex mode, wherein each copy has an image only on one side, or in a duplex mode, wherein copies have images on both sides, is described in cross-referenced patent application Ser. No. 729,453, filed Oct. 4, 1976, entitled "Copy Production Machine Having a Duplex Copy Mode".
A copy production machine having a print mode under automatic control interruptible by a copy mode is disclosed in cross-referenced patent application Ser. No. 768,651, filed Feb. 14, 1977, and entitled "Copy Production Machines". This copy production machine can be connected with a data processing system providing one input source for the information to be printed.
A given collator, e.g., as described in one of the above-referenced patent applications, satisfies a very large number of customer requirements, but obviously reaches a limit as soon as documents have to be collated, in which the number of sheets exceeds the capacity of a single collator receptacle. The collation job can be executed in two or more steps, of course, but this requires manual interaction by the operator who has to merge the collated parts of the sets. Another limitation is reached as soon as the number of sets to be collated exceeds the number of receptacles in the collator. Again, by interaction of the operator, this problem can be solved by execution of the collation job in different steps. But this operator interaction is costly and may introduce mistakes by wrongly collating sets.
It is one object of the present invention to improve the performance and capabilities of collators.
Another object is to enable execution of collation jobs which exceed the capacity of a given collator, thus providing a more efficient use of said given collator.
A further object of the invention consists in providing optimum adaption of a collator to different collation jobs.
A particular object of the invention is to enable execution of collation jobs exceeding the capacity of each single collator bin.
Another particular object is to enable execution of collation jobs exceeding the total capacity of the collator.
A further object is to provide a versatile and adaptive copier/collator combination, obtaining the aforementioned objects.
An additional object is to extend the automatic operation during duplex copying of a copier combination.
Generally speaking, a basic object of the present invention is to provide a method and an apparatus for controlling the operation of a sheet collator utilizing information as to the number of sets to be collated and the number of sheets in each set, to achieve expanded collation capacity for a given collator.